Police officers responding to the March 12 blasts at 1644 and 1646 Park Ave. found 16-year-old Oscar Hernandez in the wreckage. He was rushed to Harlem Hospital, where he has undergone three surgeries for injuries including a tear in his liver and two broken thigh bones, his doctor said during a press conference Wednesday.

"He's doing fine mental-wise. And he reacts very well." his father, Jose Cecilio Hernandez said in Spanish, choking up at times, during the press conference at Harlem Hospital.

A psychologist has been working with the father to explain to Oscar about the explosion and loss of his sister and mother, the father added.

Dr. Arthur Cooper, the director of trauma and pediatric surgery, has been overseeing Oscar's care, which he said was furthered complicated by a preexisting skin condition that causes the teen's skin to blister.

"He is incredibly strong, as you can imagine," Cooper said. "He's been through an enormous amount."

Cooper added that he hopes Oscar, who also suffered four fractures in his lower back, will be out of the hospital and walking in time to enjoy outdoor summer activities.

Jose Cecilio Hernandez said he will remain focused on his son's recovery while the investigation continues.

"I feel very well and very strong," the father said. "We trust [Dr. Cooper and his staff] and their professionalism and we see what they're doing."

The father added that his focus has been on his son's recovery and he is not sure if or when a lawsuit may be filed on behalf of the victims' families.

The estate of Hunter College security officer Sgt. Griselde Camacho, who died in the blast, and her mother Carmen Quinones notified the city Wednesday that they intend to sue the city for a combined $40 million, according to lawyer David Lesch.

Quinones remains in the hospital with injuries suffered in the explosion. News of the pending lawsuits was first reported by the Wall Street Journal.

They claim that city was negligent for not maintaining the cast-iron gas main that supplied natural gas to the buildings, the lawyer said.

The National Transportation Safety Board finished its investigation at the explosion site and is now analyzing evidence in Washington D.C., including an 8-inch gas pipe running below Park Avenue that was found to have small leaks after tests were conducted following the explosion.

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